In a bowl, whisk together the soy sauce, water, sesame oil, brown sugar, ground ginger, red pepper flakes, minced garlic, ketchup, pineapple juice, and rice vinegar until the sugar dissolves completely. This aromatic marinade will infuse the pork with sweet, savory, and spicy Hawaiian flavors. Set aside about 3/4 cup of the marinade to use as a sauce later—you'll thicken it after cooking.

Place the pork chops in a shallow dish or zip-top bag and pour the marinade over them, reserving the portion you set aside for the sauce. Let them sit for 10 minutes at room temperature—this brief marinade won't fully cure the meat but will add surface flavor and help keep it moist. I like to massage the marinade into the chops to ensure even coating.

While the pork marinates, preheat your grill to medium-high heat (about 375-400°F) and lightly grease the grates to prevent sticking. Drain the canned pineapple rings, reserving the juice if you'd like to add it to the sauce for extra sweetness. Arrange the rings on a plate near the grill so they're ready to cook when the pork goes on.

Remove the pork chops from the marinade and place them directly on the hot grill. Cook for 3-4 minutes on the first side without moving them—this creates a nice caramelized crust that locks in flavor. Flip and cook for another 3-4 minutes on the second side. During the last minute of cooking, add the pineapple rings to the grill to warm them and add charred flavor. I find that pineapple caramelizes beautifully and complements the savory pork perfectly.

Remove the pork chops and pineapple from the grill when the pork reaches an internal temperature of 140°F (medium), then transfer to a serving plate and let rest for 4 minutes—this allows the juices to redistribute and keeps the meat tender. While the pork rests, pour the reserved marinade into a saucepan over medium-high heat and bring it to a gentle boil for 2-3 minutes to reduce and concentrate flavors. In a small bowl, mix the cornstarch with 2 tablespoons of water to create a slurry, then slowly pour it into the simmering sauce while stirring constantly until it thickens to a glossy consistency (about 1 minute).

Arrange the rested pork chops and grilled pineapple rings on a serving platter or individual plates. Pour the warm Hawaiian sauce over the top, allowing it to pool slightly around the meat and pineapple. Finish with a generous sprinkle of thinly sliced scallions for a bright, fresh garnish that cuts through the richness of the dish.